Step 1: Name the dam on the Mahanadi.
It is Hirakud Dam, built near Sambalpur in Odisha, valued for irrigation, hydroelectricity and flood control.
Step 2: Name the nuclear plant location in Uttar Pradesh.
It is Narora, in Bulandshahr district, home to one of NPCIL's major nuclear stations.
Step 3: Name the software park city and the port town.
Pune in Maharashtra houses a major Software Technology Park of India, and Kandla, also known as Deendayal Port, in Gujarat is one of the country's busiest sea ports.
So the four answers are Hirakud Dam, Narora, Pune, and Kandla.